Fox News host Sean Hannity speaks in Salt Lake City. Mr. Hannity and guest Rep. Keith Ellison got into a heated debate n his show Tuesday over who to blame for the sequester, which led to the two exchanging personal insults.

Yes, that’s the edifying discussion the Fox News host and Representative Ellison had on Mr. Hannity’s show Tuesday night. Politico is calling it “one of the most explosive and contentious arguments between an anchor and a politician in recent history.” We don’t know about that, but we’re pretty sure nobody who saw it thought they’d tuned in to “Downton Abbey” by mistake.

Here’s the background: The conservative Hannity had just played a segment in which he appeared to place the blame for the sequester on President Obama. It included clips of Mr. Obama giving two similar speeches on the question, set to the lyric song “O Fortuna,” which is the kind of thing they use as background music in “Game of Thrones.”

Ellison, a Muslim, and Hannity have clashed in the past over intemperate remarks the former had made about the Bush administration and its handling of the aftermath of the 9/11 attacks. So the lawmaker was already in the blocks, so to speak. As Hannity threw the show to him he’d already thought of the point he wanted to make in the show, no matter the question.

“Quite frankly you are the worst excuse for a journalist I have ever seen,” Ellison said.

Hannity then gets a half-smile on his face. It could be pleasure that he’s baited his guest into a showdown. It could be covering nervousness, as if he didn’t quite believe his ears.

“What?” said the Fox News host. “I didn’t hear you.”

It went downhill from there. Ellison rolled along, making the general point that he believes the Republicans more to blame for the current fiscal mess, while Hannity sort of played rope-a-dope, sitting back and occasionally throwing in a punch when his guest paused for breath.

Here’s our first reaction: This is why we dislike cable news. It isn’t that they argue. It’s that they argue about irrelevant stuff.

David Graham at The Atlantic elucidates this idea at length: Really, does it matter whose idea the sequester was at this point? We know Bob Woodward thinks it does, and he’s a journalistic god, but for us it’s like the crew of the Titanic getting into a spat about who thought it was a good idea to take the North Atlantic route while the iceberg looms in front of them.

As Mr. Graham says, both parties agreed to it and voted to approve it.

“Trying to place the blame for the sequester is both a fool’s errand and a parlor game that has consumed much of the Washington media over the last week or so, as the lack of substantive progress towards stopping the sequester has left pundits and reporters with little else to talk about,” he writes.

All that said, here’s our second reaction: What pros!

Watch them go at it. Whether Hannity had an idea that his guest would explode or not, he rolls with it pretty well. You can see that he knows he’s about to get the same kind of free media publicity that Piers Morgan got when that pro-gun guest Alex Joneswent wild on his show.

That’s why Hannity just lets it go on. If he truly wanted to argue, he’d have hit the kill button earlier. He let it last about six minutes, which is about as long as any guest interview goes before they cut to something else. In that sense, he won. He got what his producers wanted. He’s getting tons of attention today.

But Ellison is going to be hero to many on the left for his rant. And did you notice that he never stopped smiling? Yes, he ranted while trying to look unthreatening. That’s what they teach you in media appearance school. If nothing else, Ellison’s press secretary must have been proud.